#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <sys/socket.h>
#include <unistd.h>
#include <string.h>
#include <cassert>

int main(int argc,char* argv[])
{
    if(argc <=2)
    {
        printf("USAGE: %s ip_address port_number\n",basename(argv[0]));
        return 1;
    }
    const char* ip = argv[1];
    int port = atoi(argv[2]);

    struct sockaddr_in address;
    bzero(&address,sizeof(address));
    address.sin_family = AF_INET;
    inet_pton(AF_INET,ip,&address.sin_addr);
    address.sin_port = htons(port);

    int sock = socket(PF_INET,SOCK_STREAM,0);
    assert(sock >=0);

    int ret = bind(sock,(struct sockaddr*)&address,sizeof(address));
    assert(ret !=-1);

    ret = listen(sock,5);
    assert(ret !=-1);

    struct sockaddr_in client;
    socklen_t client_addrlength = sizeof(client);
    int connfd = accept(sock,(struct sockaddr*)&client,&client_addrlength);
    if(connfd < 0)
    {
        printf("errno is %d\n",errno);
    }
    else
    {
        close(STDOUT_FILENO);
        dup(connfd);
        printf("abcd\n");
        close(connfd);
    }
    close(sock);
    return 0;
}